Secondary-progressive form of multiple sclerosis: MRI changes versus clinical status

To monitor the interaction between the clinical manifestation of the secondary progressive form of multiple sclerosis (SPMS) expressed in the Expanded Disability Status Scale (EDSS) and abnormal findings in magnetic resonance imaging (MRI) of the brain. To compare a time line of brain atrophy in patients with SPMS, patients with relapsing-remitting multiple sclerosis (RRMS) and the healthy population.

Brain atrophy, volume of increased signal lesions on Fluid Attenuated Inversion Recovery Sequence (FLAIR) sequence (s.c.lesion load) and decreased signal lesions on T1 weighted sequence (s.c. black holes) were measured semi-automatically and correlated with EDSS in 12 patients. Further, we compared a time line of brain parenchyma fraction (BPF) loss in patients with SPMS, patients with RRMS and the healthy population.

In patients with SPMS, no statistical correlation was found between lesion load in FLAIR and EDSS and there was also no significant statistical correlation (p=0.1134) between the volume of "black holes" and EDSS. However, we did confirm a significant correlation between increase in brain atrophy and clinical status (p=0.0093). Comparison of patients with SPMS or RRMS and the healthy population revealed that brain atrophy progressed most rapidly in patients with SPMS.

The presence of a statistically significant difference in BPF loss between patients with SPMS or RRMS and the healthy population merits further study despite the small size of our sample. We postulate that the measurement of brain atrophy could be helpful in determining the transition of RRMS to SPMS and thereby predict the progression of the disease in the future.